Benzanthrone derivatives of pyrazolanthrone and process of preparing them



Patented Aug. 23, 1332 PATENT; OFFICE KARL WILKE," or FRANKFORT-ON-THE-MAIN-HOCHST, GERMA Y, ASSIGNOR "r0 GENERAL ANILINE WORKS, INC; on NEW YORK, N. Y., A CORPORATION or ELAQ WARE THEM

BENZANTHEONE DERIVATIVES or PYRAZOLANTHRONE AND PROCESS or PREPARING,

No Drawin Application filed March 22, 1929, Serial No. stages, at in Ga -sally September 24, 1926.

The present invention relates to benzanthrone derivatives of pyrazolanthrone and process of preparing them; it contains subjectmatter in common with my co-pending U; 'S;-patent application Serial No. 216,338 filed on August- 29, 1927.

I have found that by heating of a pyrazolanthrone' of the following general formula:

. it, it

wherein v A X stands for hydrogen or a metal, I R 'for oxygen, 7

R for hydrogen or R and R together stand for as copper'powder, copper salts, vanadium salts or the like and of an acid binding agent, such as i potassium carbonate, potassium acetate or the like.

T he new products, thus obtained, have the following probable formula:

' II\INX R2 R1 whereln X stands for a substituted or unsubstituted benzanthrone radical,

R for oxygen,

R for hydrogen or R and R together stand for c dip: s n and wherein the nuclear-hydrogen atoms of the pyrazolanthrone radical may be substituted or not by any univalent residue as for Thev mixture is then'heated tov boiling for some time in an oil bath, while stirring, until a homogeneous red salt of the lpyrazolan'r throne has been formed. After adding 35' parts of Bz-l-bromobenzanthrone and about one part of copper carbonate, the mass is stirred for another 10 hours at'boiling heat. V The benzanthronyl-pyrazolanthrone which crystallizes out on cooling and which maybe is represented by the following'formula:

crystallized from nitrobenzene, melts at 398 C(tO 400 G.' It dissolves in concentrated sulfuric acid to ayellowish-red solution withp out any fluorescence.

The condensation may in the following manner: 7 parts of potassium carbonate are finely ground in a ball mill with 150mm of nitrobenzene. ,Thereupon' the mixtureis'pouredinto a stirring appa-' ratus together with 100 parts of nitrobenzene and, after addition of 22 parts of pyrazolan also be carried 'out parts of -Bz-1-ch1oro'-Bz 2 phenylbenzanthrone of the melting point 248 C. and the (4.) Iflfor the bromobenzanthrone as used mixture is stirred atboiling heat for 8 to 10 hours; After cooling, the mass is filtered and washed with nitrobenzene, alcohol and ,water and then dried. The Bz-2-phenylbenzanthronyl-pyrazolanthrone, thus prepared, has the formula and forms a yellowfcrystalline powder, which can be recrystallized from a large quantity of pyridine, When in a pure state, it di ssolves. in concentrated sulfuric acid to r a yellowish redsolution without any fluoresnce i (3) ;If for the pyrazolanthrone used in Example l are substituted 23.5 parts of 4:- methylpyrazolanthrone (comp. Berichte der deutschen Chemischen Gresellschaft, vol. 55, page 2162) ;and otherwise the procedure as set forth in Example 1 is followed, the benzanthronyll-methylpyrazolanthrone of the formula:

is obtained, which, when recrystallized from nitrobenzene, forms .a brownish-yellow powdervmelting at 332? C. to333 0.. In. concentrated sulfuric acid the product dissolves to a brownish-red solution without any fluoin Example 1 therearejsubstituted 35.5 parts of nitrated -aBz l-bromobenzanthrone which has its melting point ,at 292 C. (comp. U. S.

; ,patent application, filedune 21 1926 unoter Serial No. 117,568), a nitrobenzanthronylpyrazolanthrone of the formula: V

. GNCW l i l V O is produced. This compound forms a red-1,,

dish-yellow powder which, on recrystallization from a large quantity of nitrobenzene,

melts at 404 C. to 105C; It dissolves in concentrated sulfuric acid to a reddishyellow solution with no fluorescence.

Byreducing this nitro body, for instance].

by means of stannous chloride in a mixture of glacial acetic acid and hYdIOOhlOIlQfiCld'Y a red aminobenzanthronyl-pyrazolanthrone is formed which melts at 417 C, andis soluble in concentrated sulfurichacid with a reddish-yellow color.

(5) By condensing 282 parts of dipyrazolanthrone (comp. Berichte der deutschen Chemischen Gesellschaft, vol. 45, page 2246) or corresponding parts'of the dipotassium salt of this compound with 620 parts of Bzl-bromobenzanthroneaccording to the meth:

0d indicated in Example 1, there is easily obtained a dibenzanthronyl-dipyrazolanthrone of the formula: V

This body can be recrystallized from a large quantity of nitrobenzene. It then forms an orange-brown crystalline powder which, even when heated up to 450 Cl, does not-melt.

In concentrated sulfuric acid it'dissolves to a reddish-yellow solution. (6) 22 parts of pyrazolanthrone, 22 parts of potassium acetate, 31 parts of Bz-l-bromobenzanthrone and one part of copper acetate are boiledin the reflux condenser for about 8 hours, while stirring, in 250 parts of nitrobenzene. After cooling. the mass is filtered, washed first with nitrobenzene and then with alcohol and water and dried. The resulting product is identical with that obtained according to Example 1.

(7) If the Bz-l-bromobenzanthrone used in Example 1 and Example 6 respectively isi,

replaced by 26.5 parts -of 2-chloro -benz anthrone there is likewise obtained in aneasy, manner and with a good yieldtheuisomeric Q benzanthronyl Py 1 pyrazolanthrone of the formula:

It'forms a yellow crystalline powder which. melts at 398 C. to 400 C. and dissolves 'in' concentrated sulfuric acid to a yellowish-red solution. lVhen mixed with the similar Bz-lbenzanthronyl-Py-1-pyrazolanthrone obtained in Examples 1 and 6, the degree of the melting point is considerably lowered.

I claim:

1. The process which comprises heating a pyrazolanthrone of the following general formula:

, wherein X stands for hydrogen or a metal, R for oxygen,

R for hydrogen or R and R together stand for Lt-X with a halogen-benzanthro-ne preferably in the presence of a catalyst capable of promoting the splitting ofi of hydrogen halide and also in the presence of an inert organic solvent and an acid-binding agent.

2. The process which comprises heating to boiling a pyrazolanthrone of the following general formula:

wherein X stands for hydrogen or a metal, R for oxygen, R for hydrogen or R and R together stand for with a halogen-benzanthrone preferably in the presence of a copper catalyst and also in the presence of nitrobenzene and potassium carbonate.

3. The process which :conIPrisesheating a pyrazolanthrone of the following formula:v a rwherein I X stands for a potassium atom,

R foroxygen, I

R for hydrogen or r R and R together stand for 1LI-II\I'X, with a halogen-benzan'throne preferably in the presence of a copper catalyst and also in the presence of nitrobenzene'and potassium carbonate. v

5. The process which'comprises heating a pyrazolanthrone of the following formula:

wherein X stands for a potassium atom, R for oxygen, x R for hydrogen or R and R together stand for lH'HI, with a Bz-l-halogen-benzanthrone preferably in the presence of a catalyst capable of promoting the splitting'off of hydrogen halide and also in the presence of an inert organic solvent and an acid-binding agent.

61. The process which comprises heating to boiling pyrazolanthrone of the following formula: 1 7 v V wherein X stands for a potassium atom, R for oxygen, R for hydrogen or R and R together stand for with a Bz-1-halogen-benzanthrone preferably in' the presence of a copper catalyst and also in the presence of nitrobenzene and p0- tassium carbonate. I

7. The process which comprises heating to boiling the potassium salt of pyrazolanthrone with Bz-l-bromo-benzanthrone in the presence of copper carbonate, nitrobenzene and potassium carbonate. 8. As new products, compounds o-f the following general formula:

i, t wherein X stands for a benzanthrone radical,- R for oxygen, R for hydrogen or R and R together stand for tal-X.

following formula:

wherein X stands for 5 bound in Bz-l-position,

R for oxygen, R for hydrogen or r I R and R together stand for Y 10. As anew product, Bz-l-benzanthronyIbPy l-pyrazolanthrone which crystallizes 9. As new products, compounds of the from nitrobenzene in the form of a yellowish low crystalline powder melting at 398 C. to

400 (Land dissolving in concentrated sulfuric acid to a yellowish-red solution.

In testimony whereof, I afliX my signature.

' KARL WILKE. 

